为解决传统边界元法因其系数矩阵的存储量与求解未知量成平方关系,因而受计算机内存的限制无法求解剖分量巨大的大规模块状土壤下地网接地参数计算问题,提出用快速多极子边界元法进行求解,利用建立三维自适应八叉树的存储结构代替传统的系数矩阵存储形式。与传统边界元法相比,存储量大大减少,计算效率也明显提高。对小规模块状土壤接地模型进行编程计算,通过与传统边界元法及CDEGS软件计算结果进行对比,证实了所提方法的正确性和高效性。对大规模块状土壤接地问题算例进行编程计算,证明了所提算法在求解大规模块状土壤接地问题上的优势,为进一步研究更加复杂的块状土壤接地问题提供了参考。
The fast multipole boundary element method was proposed to solve the problems of large grounding grid under soil with massive texture parameters calculation which can not be worked out by the traditional boundary element method, whose required memory space for the coefficient matrix is squared with unknowns and limited by the available memory resources of computers. Compared to the traditional boundary element method, the memory space is reduced greatly by means of a three-dimensional adaptive octree storage structure which replaces the traditional storage schema based on coefficient matrix, and the computational efficiency is increased largely. In this paper, a small soil with massive texture grounding model was calculated and the accuracy as well as the efficiency of this method was confirmed by the comparison with traditional boundary element method and CDEGS. The advantage of the fast multipole boundary element method in solving large soil with massive texture grounding problems was tested by an example, which provides a direction for the further study of more complex grounding problems under soil with massive texture.